Recycling titanium from Ti-waste by a low-temperature extraction process

In the commercial chloride process, titanium is extracted from Ti concentra tes at high temperatures (800-1,500 degreesC), and the high-purity rutile i s the primary raw material. Chlorination at high temperatures results in hi gh-energy consumption, rapid corrosion of equipment pipelines and control s ystem, and agglomeration of the solid bed by the liquid byproducts. The hig h-purity rutile is expensive and its natural deposit is being depleted. The refore, a low-temperature Ti extraction process using Ti-waste as the prima ry raw material is highly desirable. Thermodynamic equilibrium simulation o f the reaction system shows that the extraction of Ti from Ti waste is feas ible at a temperature as low as 200 degreesC. In this study, a simple techn ology was used to remove diffusion barriers, and a low-temperature chloride process was developed. The chlorination reaction operates at 300 - 350 deg reesC, and Ti-waste can be used to replace the expensive rutile. Up to 80% of the titanium can be recycled in 5 min at 350 degreesC. The extraction of other components has a relatively low extent, so a selective extraction of Ti can be achieved. A fluidized-bed reactor was used for the chlorination process. The formation of an activated TiO2-C-Cl complex on the TiO2/C inte rface accounts for the gas-solid-solid reaction mechanism.